Apparatus for the production of undamped electrical vibrations.



S. BISENSTEIN.

APPARATUS FOR THE PRODUCTION OF UNDAMPED ELECTRICAL VIBEATIONS. APPLIOATION FILED MAR. 27, 1908.

921,526. Patented May 11,1909.

' WITNESSES: [NV {0 f if; wm mm/Z/a flfi I ATTORNEYS.

.SIMON EISENSIEIN, OF KIEF, RUSSIA.

APPARATUS FOR THE PRODUCTION OF UNDAMPED ELECTRICAL VIBRATIOL TS.

Specifications of Letters Patent.

Patented May 11, 1909.

Application filed March 27, 1908. Serial No. 423,639.

To all whom it may concern:

Be it known that I, SIMON EIsENsTEIN, a subject of the Czar of Russia, residing in Kief, in said Empire of Russia, have invented new and useful Improvements in Apparatus for the Production of Undamped Electrical Vibrations, of which the following is a'specification.

Asis known, Simon and Reich have pro posed to employ a mercury vapor lamp connected in accordance with Duddells method for the purpose of producing undamped electrical vibrations. (See Electrotechnische Zeitschrift, Berlin, 1904.) It has, however,

been found, that with a normal working tension of 100 to .1000 volts, the voltaic are be comes extinguished immediately the vibrations begin. The reason for this is that the vapor path very speedily loses its ionization so that re-kindling of the arc cannot take place. In spite of the fact that the employment of such metallic oscillators is thus connected with certain drawbacks, on the other hand there-is no doubt that they are especially advantageous for the production of undamped vibrations in as much as the consumption of the electrodes need hardly be taken into account. Now my experiments have shown that certain sparking paths, such for example as a VVehnelt cathode ray tube in all respects fulfil the conditions for operating such oscillators for the production of undamped vibrations. Wehnelt cathode ray tubes of this kind comprise cathodes consistingof a thin sheet of platinum the surface of which is coated with a layer of oxids of the rare earths; the anode is an iron pin and the whole is arranged in a high vacuum.

The accompanying drawing illustrates diagrammatically an apparatusv arranged according to the invention.

In the drawing 1 is a so-ealled Wehnelt cathode ray tube, which consists or a glass vessel from which the air has been exhausted and in which on thin Wires is placed the cathode 2, which is formed of a thin platinum membrane, and the anode 3, which is formed of an iron pin. The cathode 2 is coated with oxids of the rare earths, for instance, alkali oxids. 'The cathode ray tube is connected with the mains 6 and 7 of the exciting current, and the anode 3 is connected directly with the line current 6 and the cathode 2 over the choking coil 5 with the line current 7. The second pole of the cathode is connected through the resistance 4 with the line current 6. With this arrangement the cathode ray tube 1 acts as the exciter of the vibrations, the vibrations being generated in a shunt-circuit in which is placed the selfinductor 8 and a capacity 9 in the same manner as is usual in the Duddell switch.

The coat of oxids of the rare earths on the platinum plate 2 of the cathode, when. heated, maintains the interior of the tube highly ionized, so that the voltaic arc is kindled even when only a relatively small tension is used between the cathode and anode. In conformity' with the Duddell system of connections the self induction coil. 8 and the capacity 9 are mounted in parallel with the cathode and the anode of the VVehnelt cathode ray tube. As already stated, experiments undertaken with this tube have proved that the defects heretofore inherent in mercury vapor lamps as regards the production of undamped electrical vibrations are avoided, so that they are particularly adapted for this purpose.

What I claim as my invention and desire to secure by Letters Patent is 1. In apparatus for the production of undamped vibrations. an oscillator comprising avacuum-tube, an anode in said tube, and a cathode within the same coated with oxids of the rare earths.

2. In apparatus for the production of undamped vibrations, an oscillatorcomprising a vacuum-tube having a cathode formed of a platinum sheet coated with alkali oxids.

3. In apparatus for the production of undamped vibrations, an oscillator comprising a cathode ray tube the cathode of which is coated with alkali oxids, an anode in said tube, and a self-induction coil and capacity arranged in shunt with the cathode and anode.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

SIMON EISENSTEIN.

Witnesses:

PETER ZRAzEwsKI, H. A. LOVIAGUNIE. 

